Interpretation ID: nht87-2.2
TYPE: INTERPRETATION-NHTSA
DATE: 06/08/87
FROM: ROSE TALISMAN -- JOAN FABRICS CORP
TO: DOUG COLE -- NATIONAL VAN CONVERSION ASSOC., INC.
TITLE: NONE
ATTACHMT: ATTACHED TO LETTER DATED 11/01/88 FROM ERIKA Z JONES TO DOUG COLE; REDBOOK A32, STANDARD 302; LETTER DATED 06/29/87 FROM JONATHAN JACKSON TO DOUG COLE; LETTER DATED 06/22/87 FROM ROSE M. TALISMAN TO DOUG COLE; LETTER DATED 06/23/87 FROM DOUG CO LE TO STEVE KRANTZKE
TEXT: Dear Mr. Cole:
In accordance with our understanding from Mr. Irving Brown of C.M.I. Automotive, we are sending to your attention the specifications from both Ford Motor Company and General Motors in Detroit regarding the specific testing procedures required for meeting their codes for fire retardancy.
As you are well aware, we have run correlation studies on our pattern Passport with your recommended testing agency, Commercial Testing Company of Dalton Georgia. The test results have indicated a specific difference in correlation depending on the test method utilized. The method utilized and recommended to us by both Ford Motor Company and General Motors which requires the use of heat resistance support wires as stated on the attached specification are the direct guidelines we utilized in testing al l fabric designated for motorized product from our mill.
We certainly would be happy to discuss the rational and our specific methods for testing based on Detroit's specific requirements. Do not hesitate to call if you have any questions or need additional information.
Ford Laboratory Test Methods;
FLAMMABILITY TEST FOR AUTOMOTIVE INTERIOR MATERIALS
II. Small Parts (contd.)
A surrogate test plaque specimen made with a composition identical to that of the component material(s) shall be produced in the shape of a rectangle 4 inches (100 mm) wide, 14 inches (356 mm) long and the minimum thickness of the component up to 1/2 inch (12.7 mm) maximum, employing the same or equivalent process as used to produce the component part. The thickness of the plaque is that of the material as utilized in the vehicle except where it exceeds 1/2 inch (12.7 mm). In those applications, th e plaque is to be reduced to a uniform thickness of 1/2 inch (12.7 mm) to include the surface material exposed to the occupant compartment air space.
Test Procedure 1. Prior to testing, each specimen is conditioned for 24 hours at a temperature of 73.4 +/- 3.6 degrees F (23.0 +/- 2.0 degrees C) and 50 +/- 5% relative humidity and the test is conducted under those conditions.
2. Material is placed in the specimen holder as indicated below and tested in the direction (transverse or longitudinal) that produces the most adverse results. The specimen is oriented so that the surface closest to the occupant compartment air spa ce faces downward on the test frame.
(a) The standard test specimen (4 x 14 in (100 x 356 mm) x thickness) is inserted between two matching U-shaped frames (specimen holder) so that both sides of the specimen are held by the frames. The temperature of the frame in Figure 4 at the start of each test shall not exceed the conditioned temperature as stated above in Paragraph 1 of Test Procedure.
(b) Where the maximum available width of the specimen is 2 in (50 mm) or less so that the sides of the specimen cannot be held in the two matching U-shaped frames, it is to be supported by the use of 10 mil (0.25 mm) wires spanning the top surface of the bottom U-shaped frame at 1 in (25 mm) intervals, keeping such specimens from bending away from the horizontal at the flaming end, thereby allowing a more uniform and constant burn rate (see Figure 5). The bottom U-shaped frame shall always be positi oned so that the wires are "sandwiched" between the top and bottom frames.
(c) Samples tested with support wires: Flexible specimens, such as genuine leather, supported and unsupported vinyls, textile and backing fabrics, foams, textile padding[Illegible Word] compounds, etc., that frequently soften and bend at the flaming e nd so as to cause a non-uniform, uneven burn rate.
Samples tested without wires: Less flexible materials such as paperboard, carpets, rigid plastics, etc., seldom soften and bend at the flaming end; therefore, do not justify or necessitate support wires.
(d) Adjust ventilation hood door opening to approximately 23 in (580 mm) and regulate ventilation up to 110 CFM (0.052 m<3>/s) maximum air flow to prevent smoke and fumes from entering room. 3>